Comparative study of the pre-growing of Heterobranchus bidorsalis and Clarias gariepinus under the same diet in captivity

Abstract

This experiment was carried out from August 31 to November 8, 2022 in order to compare the growth performance of fry of two species of catfish, Heterobranchus bidorsalis and Clarias gariepinus. The fry of the two species were reared for 70 days in two above-ground tanks of 6 m³ each. They were installed under a shed with a stocking density of 20 individuals. The fish were fed twice a day (9 and 16 h) with the feed skretting of 2.2 mm diameter at a rate of 7% of their body weight for the two first weeks. This ration was readjusted every two weeks according to the growth of the fish. After 70 days of rearing, the results show that the highest (321.5 g) weight is recorded for Clarias gariepinus as well as the best value of food conversion index (1.42). After the two first weeks, the feed topffeds 4,4 mm and blue crown 6 mm were given to the fish. About the weight-length relationship, the result for the two species indicates a positive allometries with a correlation coefficient of r²>0,50. It appears from this experiment that Clarias gariepinus has the best zootechnical performances than Heterobranchus bidorsalis in the pre-growth phase.

Keywords: Fry, Skretting, Heterobranchus bidorsalis, Clarias gariepinus, zootechnical performance, Niger